Power controller for supercapacitor

ABSTRACT

A power controller, including a supercapacitor, a motor, a switching tube, an annunciator, an output resistor, a sampling resistor, a filter capacitor, a voltage-stabilizing circuit, a fly-wheel diode, and a switch. The supercapacitor, the motor, the switching tube and the sampling resistor are connected in series to form a main working circuit. The signal output end of the annunciator is connected to a trigger electrode of the switching tube via the output resistor. The sampling end of the annunciator is connected to the sampling resistor. The motor is connected in parallel to the fly-wheel diode. The sampling resistor is connected in parallel to the filter capacitor. The Vcc end of the annunciator is connected to the supercapacitor via the voltage-stabilizing circuit. The state control ends of the annunciator are connected to the GND or Vcc of the annunciator via the switch.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of International PatentApplication No. PCT/CN2014/000591 with an international filing date ofJun. 17, 2014, designating the United States, now pending, and furtherclaims priority benefits to Chinese Patent Application No.201410118400.2 filed Mar. 27, 2014. The contents of all of theaforementioned applications, including any intervening amendmentsthereto, are incorporated herein by reference. Inquiries from the publicto applicants or assignees concerning this document or the relatedapplications should be directed to: Matthias Scholl P.C., Attn.: Dr.Matthias Scholl Esq., 245 First Street, 18th Floor, Cambridge, Mass.02142.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a power controller for supercapacitors.

2. Description of the Related Art

Supercapacitors contain a large number of charges and thus can be usedas a power supply for small power motors for short-time operation.However, compared with chemical cells, supercapacitors have relativelylow volume and capacity, as well as the following disadvantages: 1. theterminal voltage change rate of chemical cells is often less than 15%,while that of a supercapacitor often reaches 80-90% of the rated value;2. the initial voltage of a supercapacitor cannot be too high, or themotor will malfunction; and 3. the working conditions of the motor, suchas rotational speed and power output, cannot be regulated.

SUMMARY OF THE INVENTION

In view of the above-described problems, it is one objective of theinvention to provide a power controller for supercapacitors whichenables a motor equipped therewith to work smoothly and steadily, underadjustable working conditions.

To achieve the above objective, in accordance with one embodiment of theinvention, there is provided a power controller for supercapacitorscomprising a supercapacitor, a motor, a switching tube, an annunciator,an output resistor, a sampling resistor, a filter capacitor, avoltage-stabilizing circuit, a fly-wheel diode, and a switch. Thesupercapacitor, the motor, the switching tube and the sampling resistorare serially connected to form a main working circuit; a signal outputend of the annunciator is connected to a trigger electrode of theswitching tube via the output resistor; a sampling end of theannunciator is connected to the sampling resistor; the motor isconnected in parallel to the fly-wheel diode; the sampling resistor isconnected in parallel to the filter capacitor; a Vcc end of theannunciator is connected to the supercapacitor via thevoltage-stabilizing circuit; and state control ends of the annunciatorare connected to a GND or Vcc of the annunciator via the switch.

In a class of this embodiment, the supercapacitor, the motor, and theswitching tube are serially connected to form the main working circuit;and the sampling resistor of the annunciator is connected to a positivepole of the supercapacitor.

In a class of this embodiment, the state control ends of the annunciatorare adjustable in number.

Advantages of the power controller for supercapacitors according toembodiments of the invention are summarized as follows. The motor isconnected in parallel to the fly-wheel diode, and the Vcc end of theannunciator is connected to the supercapacitor via thevoltage-stabilizing circuit, so that the motor can work smoothly andsteadily under adjustable working conditions, and the supercapacitor canoutput more energy. In addition, the state control ends of theannunciator are connected to a GND or Vcc of the annunciator via theswitch, so the number thereof can increase or decrease.

Take a small power motor as an example. The motor has a rated voltage of3.6 V and is adapted to direct charging and direct discharging. Twosupercapacitors are serially connected with each having a withstandvoltage of 2.7 V and capacitance of 180 F, so the total capacitance is180 F×2=360 F. Upon charging, the maximum charging voltage of eachcapacitor is 2.3 V, so the total charging voltage of the twoserially-connected capacitors is 4.6 V. The more high voltage will burnthe motor. During working, the voltage of the supercapacitor decreasesgradually from 4.6 V to 3 V until the motor stops working. In theinitial stage of the working, the motor works under excess voltage, therotational speed is fast, which will affect the service life of themotor, and with the rotational speed decreasing, the working becomesunsteadily. In such conditions, the discharged energy of thesupercapacitor is: P₁=0.5×C×U²=0.5×(180÷2)×(4.6²−3²)=547.2 J. If themotor is combined with the power controller of invention, and threesupercapacitors are serially connected with each having a capacitance of120 F, the total capacitance is 120 F×3=360 F. Upon charging, themaximum charging voltage of each capacitor is 2.7 V, so the totalcharging voltage of the three serially-connected capacitors is 8.1 V. Insuch conditions, the discharged energy of the supercapacitor is:P₁=0.5×C×U²=0.5×(120÷3)×(8.1²−3²)=1132.2 J. Take the voltage-stabilizingloss into account, about 5%, the actual discharged energy of thesupercapacitor is: 1132.2×0.95=1075.6 J. The energy ratio of thesupercapacitors of the two modes is: 1075.6÷547.2=1.97. In addition, thepower controller can ensure the motor works in rated conditions most ofthe time, thereby preventing the excess voltage, and the switch K canalso alter the working conditions of the motor.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an electrical schematic diagram of a current sampling inaccordance with one embodiment of the invention; and

FIG. 2 is an electrical schematic diagram of a voltage sampling inaccordance with one embodiment of the invention.

In the drawings, the following reference numbers are used: C1.Supercapacitor; C2. Filter capacitor; R1. Output resistor; R2. Samplingresistor; H. Motor; Q. Switching tube; A. Annunciator; W.Voltage-stabilizing circuit; D. Fly-wheel diode; K. Switch.

DETAILED DESCRIPTION OF THE EMBODIMENTS

For further illustrating the invention, experiments detailing a powercontroller for supercapacitors are described below. It should be notedthat the following examples are intended to describe and not to limitthe invention.

As shown in FIG. 1, a power controller for supercapacitors comprises asupercapacitor C1, a motor H, a switching tube Q, an annunciator A, anoutput resistor R1, a sampling resistor R2, a filter capacitor C2, avoltage-stabilizing circuit W, a fly-wheel diode D, and a switch K. Thesupercapacitor C1, the motor H, the switching tube Q and the samplingresistor R2 are serially connected to form a main working circuit. Asignal output end 1 of the annunciator A is connected to a triggerelectrode of the switching tube Q via the output resistor R1; a samplingend 2 of the annunciator A is connected to the sampling resistor R2; themotor H is connected in parallel to the fly-wheel diode D; the samplingresistor R2 is connected in parallel to the filter capacitor C2; a Vccend of the annunciator A is connected to the supercapacitor C1 via thevoltage-stabilizing circuit W; and state control ends 3, 4, 5 of theannunciator A are connected to a GND or Vcc of the annunciator via theswitch K.

During working, the switching tube Q is turned on, and thesupercapacitor C1 discharges via the motor H, the switching tube Q, andthe sampling resistor R2. When the switching tube Q is turned off, thecircuit disconnects, and the supercapacitor C1 stops discharging. Thetrigger electrode of the switching tube Q is controlled by the signaloutput end 1 of the annunciator A. The signal output end 1 of theannunciator A outputs square wave with adjustable duty ratio. The largerthe duty ratio of the square wave, the longer the discharging time ofthe supercapacitor C1; the smaller the duty ratio of the square wave,the shorter the discharging time of the supercapacitor C1. As a result,the output power of the supercapacitor C1 is adjustable. Because thesupercapacitor C1 is serially connected to the motor H, the power of themotor H is also adjustable. The sampling end 2 of the annunciator A isconnected to the sampling resistor R2, when the output current of thesupercapacitor C1 is relatively large, the voltage of the samplingresistor R2 increases accordingly. Through the feedback of the feedbackcircuit in the annunciator A, the duty ratio of the signal output end 1is decreased, so that the output current of the supercapacitor C1returns to a normal level, vice versa. For an inductive load motor, itis practicable to change the output frequency to adjust the current. Bycontrolling the switch K to connect to the state control end 3, 4, or 5of the annunciator A, the feedback circuit in the annunciator A can beselected, thereby controlling the working conditions of the motor, suchas rotational speed, power and intermission working mode. The statecontrol ends of the annunciator are adjustable in number. In thisexample, the number is three. The other end of the switch K is connectedto a GND or Vcc of the annunciator via the switch. In this example, theswitch K is connected to GND. The voltage-stabilizing circuit isconfigured to supply stable working voltage and reference voltage forthe annunciator A, independent of the voltage alteration of thesupercapacitor C1. The voltage-stabilizing circuit is a three-terminalvoltage regulator or zener diode. The filter capacitor C2 can filter outsignal fluctuation of the sampling resistor R2 thereby ensuring thesampling signal is smooth, steady, and accurate. The fly-wheel diode Dis configured to protect electronic components and feedback the energy.When the switching tube Q is turned off, high self-induced voltage willbe generated. The fly-wheel diode D can absorb the energy and feedbackit to the circuit. The annunciator A can be selected from CPU,operational amplifier, digital integrated circuit, etc. The switchingtube can be a field-effect transistor.

As shown in FIG. 2, the supercapacitor C1, the motor H, and theswitching tube Q are serially connected to form a main working circuit,and the sampling end 2 of the annunciator A is connected to a positivepole of the supercapacitor C1. In working, when the voltage of thesupercapacitor C1 decreases gradually, so does the voltage of thesampling end 2. Through the feedback of the feedback circuit in theannunciator A, the duty ratio or frequency of the signal output end 1 isadjusted, so that the output current of the supercapacitor C1 returns toa normal level.

While particular embodiments of the invention have been shown anddescribed, it will be obvious to those skilled in the art that changesand modifications may be made without departing from the invention inits broader aspects, and therefore, the aim in the appended claims is tocover all such changes and modifications as fall within the true spiritand scope of the invention.

The invention claimed is:
 1. A power controller, comprising: a) asupercapacitor; b) a motor; c) a switching tube; d) an annunciator; e)an output resistor; f) a sampling resistor; g) a filter capacitor; h) avoltage-stabilizing circuit; i) a fly-wheel diode; and j) a switch;wherein the supercapacitor, the motor, the switching tube and thesampling resistor are connected in series to form a main workingcircuit; a signal output end of the annunciator is connected to atrigger electrode of the switching tube via the output resistor; asampling end of the annunciator is connected to the sampling resistor;the motor is connected in parallel to the fly-wheel diode; the samplingresistor is connected in parallel to the filter capacitor; a Vcc end ofthe annunciator is connected to the supercapacitor via thevoltage-stabilizing circuit; and state control ends of the annunciatorare connected to a GND or Vcc of the annunciator via the switch.
 2. Thepower controller of claim 1, wherein the state control ends of theannunciator are adjustable in number.
 3. A power controller, comprising:a) a supercapacitor; b) a motor; c) a switching tube; d) an annunciator;e) an output resistor; f) a voltage-stabilizing circuit; g) a fly-wheeldiode; and h) a switch; wherein the supercapacitor, the motor, and theswitching tube are connected in series to form a main working circuit; asignal output end of the annunciator is connected to a trigger electrodeof the switching tube via the output resistor; a sampling end of theannunciator is connected to a positive pole of the supercapacitor; themotor is connected in parallel to the fly-wheel diode; a Vcc end of theannunciator is connected to the supercapacitor via thevoltage-stabilizing circuit; and state control ends of the annunciatorare connected to a GND or Vcc of the annunciator via the switch.
 4. Thepower controller of claim 3, wherein the state control ends of theannunciator are adjustable in number.